Cars are not only getting wider, longer and taller, they are also getting heavier.

With a pothole crisis in the UK and a lack of funding to pay for the necessary repairs, some experts. are calling for increased tax levied on the owners of heavier vehicles.

This, in turn, could penalise EV owners just as the government. tries to encourage more people to buy electric, as well as larger families who require bigger and heavier vehicles.

Weighing in to the debate

In response to the increasing prevalence of larger, heavier vehicles on British roads, particularly SUVs (Sports Utility Vehicles) and electric vehicles (EVs), there is a mounting call for the UK to adjust road taxation and parking fees based on vehicle weight.

Advocates argue that such measures would address environmental concerns, infrastructure wear, and urban space challenges.​

The UK has witnessed a significant surge in the sale of large vehicles, especially ion the form of SUVs.

Research from the Clean Cities campaign indicates that over 1 million cars sold annually since 2021 exceed standard urban parking dimensions, totalling approximately 4.6 million oversized vehicles.

In 2024 alone, a record 1,213,385 such cars were sold. ​

This trend, often referred to as “carspreading,” has led to 33% of new car registrations in 2024 being SUVs, up from 12% a decade earlier.

These vehicles contribute to increased road damage, parking infrastructure strain, and heightened risks in crashes, especially for pedestrians and cyclists. ​

Wear and tear

Studies have demonstrated that heavier vehicles, such as SUVs and EVs, cause disproportionately more damage to road surfaces compared to lighter vehicles.

The “fourth power law” in engineering indicates that the damage inflicted on roads increases exponentially with vehicle weight.

For instance, a vehicle twice as heavy as another can cause up to 16 times more road damage. ​

Research led by the University of Leeds found that the average electric car imposes 2.24 times more stress on roads than its petrol equivalent, and 1.95 times more than a diesel vehicle.

Larger electric vehicles weighing over 2,000kg cause up to 2.32 times more wear.

This increased stress accelerates the formation of small cracks in asphalt, which can expand into potholes if left unaddressed. ​

The Asphalt Industry Alliance has expressed concerns that unclassified roads, not designed to accommodate heavy goods vehicle axle weights, may deteriorate more rapidly under the strain of heavier cars, particularly EVs.

Weight and wallets

Emissions experts Nick Molden and Felix Leach propose a taxation system based on vehicle weight and mileage.

They argue that the current Vehicle Excise Duty (VED) system is a “mishmash of incentives and penalties” and suggest that taxing cars by weight and distance travelled would more accurately reflect their environmental impact.

Their research indicates that switching to a vehicle 150 kg lighter or driving 1,000 fewer miles could save £100 annually.​

Molden points out that a car’s weight accounts for approximately three-quarters of its environmental impact, making it a reliable metric for taxation.

This approach aims to simplify consumer choices and encourage the adoption of lighter, less polluting vehicles.​

Precedents and initiatives

Internationally, cities like Paris have implemented higher parking fees for heavier vehicles, and Lyon is set to introduce a sliding scale of parking charges based on vehicle weight.

In the UK, areas such as Bath and Islington are considering similar measures.

London Mayor Sadiq Khan has also expressed interest in adopting weight-based parking charges to address the challenges posed by large vehicles. ​

Cardiff Council is contemplating a “Land Rover tax,” proposing higher parking permit charges for vehicles exceeding 2.4 tonnes.

This initiative aims to manage limited parking space and encourage the use of smaller cars.

However, it has faced criticism from residents who view it as an anti-car measure.​

Debate and considerations

While the proposal for weight-based taxation has garnered support from environmentalists and urban planners, it also faces opposition.

Critics argue that such a system could disproportionately affect families and individuals who require larger vehicles for practical reasons.

Additionally, some contend that the focus should remain on emissions rather than weight, especially as electric vehicles, which are generally heavier, become more prevalent. ​

The UK Treasury has stated that there are no current plans to reform VED to be based solely on weight.

A spokesperson emphasised the importance of electric vehicles in decarbonising the transport sector and tackling climate change.​

Popularity growth

As the UK grapples with the environmental and infrastructural challenges posed by larger vehicles, the debate over weight-based taxation and parking charges continues.

Some believe that not only is the failure of governments over the last two decades to properly invest in and maintain the existing road network to blame for much of the pothole crisis, but that the dramatic increase in car sizes and weight has added to the woes.

SUVs have become Britain’s best-selling type of new car for the first time on record, official sales figures reveal.

A third of new cars entering the road last year were ‘Chelsea Tractors’, snatching the mantle of most popular segment from superminis, which had topped sales charts for decades.

SUVs accounted for 33% of all registrations in 2024, up from just 12% a decade earlier, according to Britain’s auto trade body.

The sales statistics also show that eight of the ten most commonly bought new cars last year were crossovers or 4X4s as once-popular conventional hatchbacks and saloons fell down the pecking order.

While the change of guard suggests a greater appetite for jacked-up vehicles, the growth in SUV sales has partly been driven by manufacturers reducing availability of small models in recent years.

 

While the proposed new measure would seem to be logical, they could potentially adversely affect the sale of more environmentally friendly. EVS, as well as being an extra tax on larger families or those needing bigger vehicles to transport the elderly or people with particular health issues.

This is seen as unfair and impractical.

However, proponents argue that such measures would promote environmental sustainability and urban safety.

The outcome of this debate is likely to significantly influence the future of vehicle taxation and urban planning in the UK.